There are many circumstances where it is desired to turn articles such as sheets of paper, flyers, signatures, booklets, books or the like as they are conveyed around a corner while maintaining the orientation of those articles relative to the conveyor. A variety of turning conveyers are available for these general purposes, including so-called slat-top chain conveyors, flat belt conveyors, live-roller conveyors and, in some circumstances, articulated segment conveyors. The latter may include interfitted articulated segments or overlapping fish-scale type segments and normally are used primarily for conveying relatively large objects.
In many of the applications for turning conveyors, it is desirable to convey articles around turns through various angles, up to at least 180.degree., with relative short turning radii to save space, and at high speeds to save time, while maintaining each article in a predetermined orientation relative to the underlying conveyor, e.g., from the input into the turn to the output from the turn. It is also desirable to minimize or avoid the need for side guides to force the product around a turn and to minimize or avoid significant banking of the conveyor as it traverses a turn. The articles being conveyed may be shingled or spaced individual items of various sizes, and may be of varying thicknesses. Accordingly, it is desirable to readily accommodate variations in the thickness as well as the size of the articles.